What we were able to demonstrate in this study is that both men and women are able to more quickly locate weapons, such as guns and knives, in a visual display, compared to locating similar non-weapon objects (such as staplers and cutlery). This effect was even more pronounced when the weapons were depicted wielded.

Finding dangerous objects (including weapons but also spiders and snakes) relatively quickly in a visual display is nothing new. Our study was unique in demonstrating that this effect is more pronounced when the weapons are depicted wielded.

The most new and exciting aspect of this study is, however, the sex difference. Across the board men were faster to locate the weapons than women were, but there were no sex differences for any of the non-weapon objects. We discussed this finding in the context of other well known violence-related sex differences: cross culturally men are far more likely than women to both instigate and be victims of physical violence, including having a virtual monopoly on same-sex homicides. We argue that the sex difference in speedy responses to weapons is related to these sex differences in propensity for violence, and that male brains and bodies evolved under stronger selection pressures to survive physical violence than did women's.

And, as the newspapers pointed out, it's not impossible that one of the side effects of these selection pressures, is that men have a small advantage in violent video games that rely on fast responses.